To radiate generated by power dissipation in a semiconductor device, a cooling measure must be taken, because natural heat radiation from the device case is insufficient, and the junction temperature exceeds the allowable limit of the device. Normally, either self-cooling, air-cooling, water-cooling, or oil-cooling methods are adopted. Described in article is how to select cooling fins and how to set a device between the cooling fins, when an air-cooling method is adopted.
Problems regarding thermal cooling are kin to those of an electrical circuit, and the resistance to the heat flow (thermal resistance) must be taken into consideration.
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